1. Field of the Invention
The present invention relates to a ratchet tool, and more particularly to a ratchet tool having a control device for effectively controlling or actuating a pawl to engage with a drive member, and for preventing the pawl from being moved or disengaged from the drive member inadvertently.
2. Description of the Prior Art
Typical ratchet tools comprise a drive member rotatably received within a head and having an engaging hole formed therein for receiving and for driving fasteners, or having a driving shank extended therefrom for engaging with and for driving the fasteners, and a pawl pivotally received or engaged within the head or the handle, and biased to engage with the drive member, in order to control the driving or rotating directions of the drive member relative to the fasteners.
For example, U.S. Pat. No. 6,260,449 to I-He discloses one of the typical ratchet tools also comprising a pawl pivotally received or engaged within a head or a handle, and biased to engage with a drive member which is rotatably received within the head, and arranged to allow the pawl either to actuate the drive member to rotate or to drive the fasteners, or to allow the fasteners to be freely rotated reversely relative to the drive member.
For actuating the pawl, a pawl actuating member is further required to be provided and pivotally received or engaged within the handle, and a spring-biased ball engaged with the pawl, in order to actuate or to force either of two end portions of the pawl to engage with the drive member, and thus to control or to determine the driving or rotating directions of the drive member relative to the fasteners.
However, a spring member is required to be disposed between the spring-biased ball and the pawl actuating member, and the spring-biased ball may have a good chance to be disengaged from the pawl actuating member, and thus may not be used to engage with and to control the drive member.
U.S. Pat. No. 6,282,991 to Hu discloses another typical ratchet tool also comprising a pawl actuating member rotatably or pivotally received or engaged within the handle, and a spring member engaged with a pawl or engaged between the pawl and the pawl actuating member, for actuating or forcing the pawl to engage with the drive member, and thus to control or to determine the driving or rotating directions of the drive member relative to the fasteners.
In Hu, the spring member includes a flexible end for directly engaging with the pawl and for actuating the pawl to engage with the drive member, in order to actuate the drive member to rotate or to drive the fasteners, or to allow the fasteners to be freely rotated reversely relative to the drive member.
However, the flexible spring member may be curved or bent relative to the pawl actuating member and the pawl, and thus may not be used to effectively actuate the pawl to engage with and to control the drive member when the pawl actuating member is rotated relative to the pawl and the drive member.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional control devices for ratchet tools.